Monocyclopentadienyl titanium metal compounds for ethylene-α-olefin-copolymer production catalysts

ABSTRACT

The invention is a catalyst system including a monocyclopentadienyl titanium compound and an alumoxane component which is highly productive for polymerizing ethylene and α-olefins to produce a high molecular weight ethylene-α-olefin copolymer having a high content of α-olefin.

This application is a Divisional of Ser. No. 08/109,194, Aug. 19, 1993,U.S. Pat. No. 5,631,391; which is a divisional of Ser. No. 07/850,751,Mar. 13, 1992, U.S. Pat. No. 5,264,405; which is a continuation-in-partof Ser. No. 07/581,841, Sep. 13, 1990, U.S. Pat. No. 5,096,867; which isa continuation-in-part of Ser. No. 07/533,245, Jun. 4, 1990, U.S. Pat.No. 5,055,438; which is a continuation-in-part of Ser. No. 07/406,945,Sep. 13, 1989, abandoned.

FIELD OF THE INVENTION

This invention relates to certain monocyclopentadienyl titaniumcompounds, to a catalyst system comprising a monocyclopentadienyltitanium compound and an alumoxane, and to a process using such catalystsystem for the production of polyolefins, particularly ethylene-α-olefincopolymers having a high molecular weight and high level of α-olefinincorporation. The catalyst system is highly active at low ratios ofaluminum to the titanium metal, hence catalyzes the production of apolyolefin product containing low levels of catalyst metal residue.

This invention relates to the discovery of various catalyst ligandstructure affects which are reflected in the activity of the catalystsystem and in the physical and chemical properties possessed by apolymer produced with a monocyclopentadienyl titanium metal catalystsystem. Accordingly, various species within the general class ofmonocyclopentadienyl titanium catalyst as disclosed by commonly-ownedU.S. patent application Ser. No. 07/581,841, have been discovered to bevastly superior in terms of the ability of such species to produceethylene-α-olefin copolymers of high molecular weight with high levelsof α-olefin comonomer incorporation and at high levels of catalystproductivity.

BACKGROUND OF THE INVENTION

As is well known, various processes and catalysts exist for thehomopolymerization or copolymerization of olefins. For many applicationsit is of primary importance for a polyolefin to have a high weightaverage molecular weight while having a relatively narrow molecularweight distribution. A high weight average molecular weight, whenaccompanied by a narrow molecular weight distribution, provides apolyolefin or an ethylene-α-olefin copolymer with high strengthproperties.

Traditional Ziegler-Natta catalyst systems—a transition metal compoundcocatalyzed by an aluminum alkyl—are capable of producing polyolefinshaving a high molecular weight but a broad molecular weightdistribution.

More recently a catalyst system has been developed wherein thetransition metal compound has two or more cyclopentadienyl ringligands—such transition metal compound being referred to as ametallocene—which catalyzes the production of olefin monomers topolyolefins. Accordingly, metallocene compounds of a Group IV B metal,particularly, titanocenes and zirconocenes, have been utilized as thetransition metal component in such “metallocene” containing catalystsystem for the production of polyolefins and ethylene-α-olefincopolymers. When such metallocenes are cocatalyzed with an aluminumalkyl—as is the case with a traditional type Ziegler-Natta catalystsystem—the catalytic activity of such metallocene catalyst system isgenerally too low to be of any commercial interest.

It has since become known that such metallocenes may be cocatalyzed withan alumoxane—rather than an aluminum alkyl—to provide a metallocenecatalyst system of high activity for the production of polyolefins.

The zirconium metallocene species, as cocatalyzed or activated with analumoxane, are commonly more active than their hafnium or titaniumanalogues for the polymerization of ethylene alone or together with anα-olefin comonomer. When employed in a non-supported form—i.e., as ahomogeneous or soluble catalyst system—to obtain a satisfactory rate ofproductivity even with the most active zirconium species of metallocenetypically requires the use of a quantity of alumoxane activatorsufficient to provide an aluminum atom to transition metal atom ratio(A1:™) of at least greater than 1000:1; often greater than 5000:1, andfrequently on the order of 10,000:1. Such quantities of alumoxane impartto a polymer produced with such catalyst system an undesirable contentof catalyst metal residue, i.e., an undesirable “ash” content (thenonvolatile metal content). In high pressure polymerization proceduresusing soluble catalyst systems wherein the reactor pressure exceedsabout 500 bar only the zirconium or hafnium species of metallocenes maybe used. Titanium species of metallocenes are generally unstable at suchhigh pressures unless deposited upon a catalyst support.

A wide variety of Group IV B transition metal compounds have been namedas possible candidates for an alumoxane cocatalyzed catalyst system.Although bis(cyclopentadienyl) Group IV B transition metal compoundshave been the most preferred and heavily investigated for use inalumoxane activated catalyst systems for polyolefin production,suggestions have appeared that mono and tris(cyclopentadienyl)transition metal compounds may also be useful. See, for example U.S.Pat. Nos. 4,522,982; 4,530,914 and 4,701,431. Suchmono(cyclopentadienyl) transition metal compounds as have heretoforebeen suggested as candidates for an alumoxane activated catalyst systemare mono(cyclopentadienyl) transition metal trihalides and trialkyls.

More recently, International Publication No. WO 87/03887 describes theuse of a composition comprising a transition metal coordinated to atleast one cyclopentadienyl and at least one heteroatom ligand as atransition metal component for use in an alumoxane activated catalystsystem for α-olefin polymerization. The composition is broadly definedas a transition metal, preferably of Group IV B of the Periodic Table,which is coordinated with at least one cyclopentadienyl ligand and oneto three heteroatom ligands, the balance of the transition metalcoordination requirement being satisfied with cyclopentadienyl orhydrocarbyl ligands. Catalyst systems described by this reference areillustrated solely with reference to transition metal compounds whichare metallocenes, i.e., bis(cyclopentadienyl) Group IV B transitionmetal compounds.

Even more recently, at the Third Chemical Congress of North Americanheld in Toronto, Canada in June 1988, John Bercaw reported upon effortsto use a compound of a Group III B transition metal coordinated to asingle cyclopentadienyl heteroatom bridged ligand as a catalyst systemfor the polymerization of olefins. Although some catalytic activity wasobserved under the conditions employed, the degree of activity and theproperties observed in the resulting polymer product were discouragingof a belief that such monocyclopentadienyl transition metal compoundcould be usefully employed for commercial polymerization processes.

Although the metallocene/alumoxane catalyst system constituted animprovement relative to a traditional Ziegler-Natta catalyst system, aneed existed for discovering catalyst systems that permit the productionof higher molecular weight polyolefins and desirably with a narrowmolecular weight distribution. Further desired was a catalyst which,within reasonable ranges of ethylene to α-olefin monomer ratios, willcatalyze the incorporation of higher contents of α-olefin comonomers inthe production of ethylene-α-olefins copolymers.

SUMMARY OF THE INVENTION

Commonly owned copending U.S. application Ser. No. 07/581,841, now U.S.Pat. No. 5,096,867, filed Sep. 13, 1990. disclosed the discovery of aclass of monocyclopentadienyl Group IV B transition metal compoundswhich, when activated with an alumoxane, may be employed as a catalystsystem in solution, slurry or bulk phase polymerization procedure toproduce a polyolefin of high weight average molecular weight andrelatively narrow molecular weight distribution.

The “Group IV B transition metal component” of the catalyst systemdisclosed in application Ser. No. 581,841 is represented by the formula:

wherein:

M is Zr, Hf or Ti in its highest formal oxidation state (+4, d⁰complex);

(C₅H_(5−y−x)R_(x)) is a cyclopentadienyl ring which is substituted withfrom zero to five substituent groups R, “x” is 0, 1, 2, 3, 4 or 5denoting the degree of substitution, and each substituent group R is,independently, a radical selected from a group consisting of C₁-C₂₀hydrocarbyl radicals, substituted C₁-C₂₀ hydrocarbyl radicals whereinone or more hydrogen atoms is replaced by a halogen radical, an amidoradical, a phosphido radical, and alkoxy radical or any other radicalcontaining a Lewis acidic or basic functionality, C₁-C₂₀hydrocarbyl-substituted metalloid radicals wherein the metalloid isselected from the Group IV A of the Periodic Table of Elements; halogenradicals, amido radicals, phosphido radicals, alkoxy radicals,alkylborido radicals or any other radical containing Lewis acidic orbasic functionality; or (C₅H_(5−y−x)R_(x)) is a cyclopentadienyl ring inwhich at least two adjacent R-groups are joined forming a C₄-C₂₀ ring togive a saturated or unsaturated polycyclic cyclopentadienyl ligand suchas indenyl, tetrahydroindenyl, fluorenyl or octahydrofluorenyl;

(JR′_(z−i−y)) is a heteroatom ligand in which J is an element with acoordination number of three from Group V A or an element with acoordination number of two from Group VI A of the Periodic Table ofElements, preferably nitrogen, phosphorus, oxygen or sulfur, and each R′is, independently a radical selected from a group consisting of C₁-C₂₀hydrocarbyl radicals, substituted C₁-C₂₀ hydrocarbyl radicals whereinone or more hydrogen atoms are replaced by a halogen radical, an amidoradical, a phosphido radical, an alkoxy radical or any other radicalcontaining a Lewis acidic or basic functionality, and “z” is thecoordination number of the element J;

each Q may be independently any univalent anionic ligand such as ahalide, hydride, or substituted or unsubstituted C₁-C₂₀ hydrocarbyl,alkoxide, aryloxide, amide, arylamide, phosphide or arylphosphide,provided that where any Q is a hydrocarbyl such Q is different from(C₅H_(5−y−x)R_(x)), or both Q together may be an alkylidene or acyclometallated hydrocarbyl or any other divalent anionic chelatingligand;

“y” is 0 or 1 when w is greater than 0; y is 1 when w is 0; when “Y” is1, T is a covalent bridging group containing a Group IV A or V A elementsuch as, but not limited to, a dialkyl, alkylaryl or diaryl silicon orgermanium radical, alkyl or aryl phosphine or amine radical, or ahydrocarbyl radical such as methylene, ethylene and the like;

L is a neutral Lewis base such as diethylether, tetraethylammoniumchloride, tetrahydrofuran, dimethylaniline, aniline, trimethylphosphine,n-butylamine, and the like; and “w” is a number from 0 to 3. L can alsobe a second transition metal compound of the same type such that the twometal centers M and M′ are bridged by Q and Q′, wherein M′ has the samemeaning as M and Q′ has the same meaning as Q. Such dimeric compoundsare represented by the formula:

The alumoxane component of the catalyst may be represented by theformulas: (R³—Al—O)_(m); R⁴(R⁵—Al—O)_(m)—AIR₆ ² or mixtures thereof,wherein R³-R⁶ are, independently, a C₁-C₅ alkyl group or halide and “m”is an integer ranging from 1 to about 50 and preferably is from about 13to about 25.

Catalyst systems may be prepared by placing the “Group IV B transitionmetal component” and the alumoxane component in common solution in anormally liquid alkane or aromatic solvent, which solvent is preferablysuitable for use as a polymerization diluent for the liquid phasepolymerization of an olefin monomer.

As further disclosed in, U.S. application Ser. No. 07/581,841, filedSep. 13, 1990, now U.S. Pat. No. 5,096,867, that class of the Group IV Btransition metal component wherein the metal is titanium have been foundto impart beneficial properties to a catalyst system which areunexpected in view of what is known about the properties ofbis(cyclopentadienyl) titanium compounds which are cocatalyzed byalumoxanes. Whereas titanocenes in their soluble form are generallyunstable in the presence of aluminum alkyls, the monocyclopentadienyltitanium metal components, particularly those wherein the heteroatom isnitrogen, generally exhibit greater stability in the presence ofaluminum alkyls, higher catalyst activity rates and higher α-olefincomonomer incorporation.

Further, the titanium class of the Group IV B transition metal componentcatalyst of the invention described by application Ser. No. 07/581,841filed Sep. 13, 1990, now U.S. Pat. No. 5,096,867, generally exhibithigher catalyst activities and the production of polymers of greatermolecular weight and α-olefin comonomer contents than catalyst systemsprepared with the zirconium or hafnium species of the Group IV Btransition metal component.

This invention comprises the discovery of a subgenus ofmonocyclopentadienyl titanium compounds which, by reason of the presencetherein of ligands of a particular nature, provide a catalyst of greatlyimproved performance characteristics compared to other members of thegenus of monocyclopentadienyl titanium compounds as described incopending U.S. application Ser. No. 07/581,841 filed Sep. 13, 1990, nowU.S. Pat. No. 5,096,867. The subgenus of monocyclopentadienyl titaniumcatalyst most preferred is that wherein the heteroatom ligand is anamido group, the nitrogen atom of which is bridged through a bridginggroup (T) to the cyclopentadienyl ring and wherein the nitrogen atom iscovalently bonded through a 1° or 2° carbon atom to an alicyclic oraliphatic hydrocarbyl group. Herein a 1° carbon atom is one which ismethyl or a carbon atom which is bonded to only one other carbon atom; a2° carbon atom is one which is bonded to only two other carbon atoms,and a 3° carbon atom is bonded to three other carbon atoms. Preferablythe alicyclic or aliphatic hydrocarbyl group has three or more carbonatoms and is bonded to the nitrogen atom through a 2° carbon atom, mostpreferably the hydrocarbyl group is alicyclic. Monocyclopentadienyltitanium compounds within this subgenus have been discovered to producea highly productive catalyst system which produces an ethylene-α-olefincopolymer of significantly greater molecular weight and α-olefincomonomer content as compared with other species of monocyclopentadienyltitanium compounds when utilized in an otherwise identical catalystsystem under identical polymerization conditions. Further, within thissubgenus of titanium compounds it has been found that the nature anddegree of substitution groups (R) of the cyclopentadienyl ring can bevaried to produce a catalyst system having a “catalyst reactivity ratio(r₁)” which may be varied from a high to a low value as may be mostdesired to best suit the catalyst system to a particular type ofpolymerization process. Particularly it has been found that as thenumber of substituents/(R), which are preferably hydrocarbylsubstituents, increases the reactivity ratio (r₁) decreases, the lowestreactivity ratios being obtained by a titanium compound having atetrahydrocarbyl substituted cyclopentadienyl group, preferably atetramethylcyclopentadienyl group.

A typical polymerization process of the invention comprises the steps ofcontacting ethylene and a C₃-C₂₀ α-olefin alone, or with otherunsaturated monomers including C₃-C₂₀ α-olefins, C₄-C₂₀ diolefins,and/or acetylenically unsaturated monomers with a catalyst comprising,in a suitable polymerization diluent, a monocyclopentadienyl titaniumcompound as described above; and a methylalumoxane in an amount toprovide a molar aluminum to titanium metal ratio of from about 1:1 toabout 20,000:1 or more; and reacting such monomers in the presence ofsuch catalyst system at a temperature of from about −100° C. to about300° C. for a time of from about 1 second to about 10 hours to produce acopolymer having a weight average molecular weight of from about 1,000or less to about 5,000,000 or more and a molecular weight distributionof from about 1.5 to about 15.0.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The disclosure of U.S. application Ser. No. 07/581,841, filed Sep. 13,1990, now U.S. Pat. No. 5,096,867, is hereby incorporated by reference.

As disclosed in U.S. application Ser. No. 07/581,841 filed Sep. 13,1990, now U.S. Pat. No. 5,096,867, wherein it is desired to produce anα-olefin copolymer which incorporates a high content of α-olefin, theclass of Group IV B transition metal compound preferred is one oftitanium. The most preferred class of titanium metal compounds arerepresented by the formula:

wherein Q, L, R′, R, “x” and “w” are as previously defined and R¹ and R²are each independently a C₁ to C₂₀ hydrocarbyl radicals, substituted C₁to C₂₀ hydrocarbyl radicals wherein one or more hydrogen atom isreplaced by a halogen atom; R¹ and R² may also be joined forming a C₃ toC₂₀ ring which incorporates the silicon bridge.

Among this class of titanium compounds various substituent and ligandaffects have been discovered which significantly affect the propertiesof a catalyst system. The nature and degree of substitutions (R) in thecyclopentadienyl ring was found to significantly influence the catalystability to incorporate α-olefin comonomers when producing anethylene-α-olefin copolymer. For the greatest amount of comonomerincorporation, the cyclopentadienyl ring should be fully substituted(x=4) with hydrocarbyl groups (R), most preferably methyl groups. Thisaffect is demonstrated by a comparison between Examples 83 to 85. Next,the nature of the R′ ligand of the amido group significantly influencesthe capability of a catalyst to incorporate α-olefin comonomer. Amidogroup R′ ligands which are aliphatic or alicyclic hydrocarbyl ligandsbonded to the nitrogen atom through a 1° or 2° carbon atom provide for agreater degree of α-olefin comonomer incorporation than do R′ groupsbonded through a 3° carbon atom or bearing aromatic carbon atoms.Further, wherein the R′ ligand is bonded to the nitrogen atom through a2° carbon atom, the activity of the catalyst is greater when the R′substituent is alicyclic than when R′ is bonded to the nitrogen througha 1° carbon atom of an aliphatic group of identical carbon number. Withregard to an alicyclic hydrocarbyl R′ ligand it has been found that asthe number of carbon atoms thereof increases the molecular weight of theethylene-α-olefin copolymer increases while the amount of α-olefincomonomer incorporated remains about the same or increases. Further, asthe carbon number of the alicyclic hydrocarbyl ligand increases theproductivity of the catalyst system increases. This is demonstrated byExamples 71-76. Accordingly, the R′ ligand most preferred iscyclododecyl (C₁₂H₂₃).

The affects of the bridging group ligands R¹ and R² has been found to beof less significance. The nature of the R¹ and R² ligands exerts a smalleffect upon the activity of a catalyst. For greatest catalyst activitythe R¹ and R² ligands are preferably alkyl, most preferably methyl. TheQ anionic ligands of the transition metal have not been observed toexert any particular influence on the catalyst or polymer properties, asdemonstrated by comparison of Examples 71 and 86. Accordingly, as aconvenience in the production of the transition metal component the Qligands are preferably chlorine or methyl.

The compounds most preferred for reasons of their high catalyst activityin combination with an ability to produce high molecular weightethylene-α-olefin copolymers of high comonomer contents is representedby the formula:

wherein R¹ and R² are each independently a C₁ to C₆ hydrocarbyl radical,each Q is independently a halide or aikyl radical, R′ is an aliphatic oran alicyclic hydrocarbyl radical of the formula (C_(n)H_(2n+b)) wherein“no” is a number from 3 to 20 and “b” is +1 in which case the ligand isaliphatic or −1 in which case the ligand is alicyclic. Of thesecompounds, the most preferred is that compound wherein R¹ and R² aremethyl, each Q is chlorine or methyl, n is 12, and the hydrocarbylradical is alicyclic (i.e., b is −1). Most preferred is that compoundwherein the (C_(n)H_(2n−1)) hydorcarbyl radical is a cyclododecyl group.Hereafter this compound is referred to for convenience asMe₂Si(C₅Me₄)-(NC₁₂H₂₃)TiQ₂.

The alumoxane component of the catalyst system is an oligomeric compoundwhich may be represented by the general formula (R³—Al—O)_(m) which is acyclic compound, or may be R⁴(R⁵—Al—O—)_(m)—AlR⁶ ₂ which is a linearcompound. An alumoxane is generally a mixture of both the linear andcyclic compounds. In the general alumoxane formula R³, R⁴, R⁵ and R⁶are, independently a C₁-C₅ alkyl radical, for example, methyl, ethyl,propyl, butyl or pentyl and “m” is an integer from 1 to about 50. Mostpreferably, R³, R⁴, R⁵ and R⁶ are each methyl and “m” is at least 4.When an alkyl aluminum halide is employed in the preparation of thealumoxane, one or more R³⁻⁶ groups may be halide.

As is now well known, alumoxanes can be prepared by various procedures.For example, a trialkyl aluminum may be reacted with water, in the formof a moist inert organic solvent; or the trialkyl aluminum may becontacted with a hydrated salt, such as hydrated copper sulfatesuspended in an inert organic solvent, to yield an alumoxane. Generally,however prepared, the reaction of a trialkyl aluminum with a limitedamount of water yields a mixture of both linear and cyclic species ofalumoxane.

Suitable alumoxanes which may be utilized in the catalyst systems ofthis invention are those prepared by the hydrolysis of atrialkylaluminum; such as trimethylaluminum, triethyaluminum,tripropylaluminum; triisobutylaluminum, dimethylaluminumchloride,diisobutylaluminumchloride, diethylaluminumchloride, and the like. Themost preferred alumoxane for use is methylalumoxane (MAO).Methylalumaxanes having an average degree of oligomerization of fromabout 4 to about 25 (“m”=4 to 25), with a range of 13 to 25, are themost preferred.

Catalyst Systems

The catalyst systems employed in the method of the invention comprise acomplex formed upon admixture of the titanium metal component with analumoxane component. The catalyst system may be prepared by addition ofthe requisite titanium metal and alumoxane components to an inertsolvent in which olefin polymerization can be carried out by a solution,slurry or bulk phase polymerization procedure.

The catalyst system may be conveniently prepared by placing the selectedtitanium metal component and the selected alumoxane component, in anyorder of addition, in an alkane or aromatic hydrocarbonsolvent—preferably one which is also suitable for service as apolymerization diluent. Where the hydrocarbon solvent utilized is alsosuitable for use as a polymerization diluent, the catalyst system may beprepared “sin situ” in the polymerization reactor. Alternatively, thecatalyst system may be separately prepared, in concentrated form, andadded to the polymerization diluent in a reactor. or, if desired, thecomponents of the catalyst system may be prepared as separate solutionsand added to the polymerization diluent in a reactor, in appropriateratios, as is suitable for a continuous liquid phase polymerizationreaction procedure. Alkane and aromatic hydrocarbons suitable assolvents for formation of the catalyst system and also as apolymerization diluent are exemplified by, but are not necessarilylimited to, straight and branched chain hydrocarbons such as isobutane,butane, pentane, hexane, heptane, octane and the like, cyclic andalicyclic hydrocarbons such as cyclohexane, cycloheptane,methylcyclohexane, methylcycloheptane and the like, and aromatic andalkyl-substituted aromatic compounds such as benzene, toluene, xyleneand the like. Suitable solvents also include liquid olefins which mayact as monomers or comonomers including ethylene, propylene, 1-butene,1-hexene and the like.

In accordance with this invention optimum results are generally obtainedwherein the titanium metal compound is present in the polymerizationdiluent in a concentration of from about 0.0001 to about 1.0millimoles/litre of diluent and the alumoxane component is present in anamount to provide a molar aluminum to transition metal ratio of fromabout 1:1 to about 20,000:1. Sufficient solvent should be employed so asto provide adequate heat transfer away from the catalyst componentsduring reaction and to permit good mixing.

The catalyst system ingredients—that is, the titanium metal component,the alumoxane, and polymerization diluent—can be added to the reactionvessel rapidly or slowly. The temperature maintained during the contactof the catalyst components can vary widely, such as, for example, from−100° to 300° C. Greater or lesser temperatures can also be employed.Preferably, during formation of the catalyst system, the reaction ismaintained within a temperature of from about 25° to 100° C., mostpreferably about 25° C.

Polymerization Process

In a preferred embodiment of the process of this invention the catalystsystem is utilized in the liquid phase (slurry, solution, suspension orbulk phase or combination thereof), high pressure fluid phase or gasphase polymerization of an olefin monomer. These processes may beemployed singularly or in series. The liquid phase process comprises thesteps of contacting an ethylene and an α-olefin monomer with thecatalyst system in a suitable polymerization diluent and reacting themonomers in the presence of the catalyst system for a time and at atemperature sufficient to produce an ethylene-α-olefin copolymer of highmolecular weight.

The monomers for such process comprise ethylene in combination with anα-olefin having 3 to 20 carbon atoms for the production of anethylene-α-olefin copolymer. It should be appreciated that theadvantages as observed in a ethylene-α-olefin copolymer produced with acatalyst system of this invention would also be expected to be obtainedin a copolymer of different α-olefins wherein ethylene is not used as amonomer as viewed in comparison to a copolymer of the same or differentα-olefins produced under similar polymerization conditions with acatalyst system which does not use a monocyclopentadienyl titaniumcompound as defined herein. Accordingly, although this invention isdescribed with reference to an ethylene-α-olefin copolymer and theadvantages of the defined catalyst system for the production thereof,this invention is not to be understood to be limited to the productionof an ethylene-α-olefin copolymer, but instead the catalyst systemhereof is to be understood to be advantageous in the same respects tothe production of a copolymer composed of two or more C₃ or higherα-olefin monomers. Copolymers of higher α-olefin such as propylene,butene, styrene or higher α-olefins and diolefins can also be prepared.Conditions most preferred for the homo- or copolymerization of ethyleneare those wherein ethylene is submitted to the reaction zone atpressures of from about 0.019 psia to about 50,000 psia and the reactiontemperature is maintained at from about −100° to about 300° C. Thealuminum to titanium metal molar ratio is preferably from about 1:1 to18,000 to 1. A more preferable range would be 1:1 to 2000:1. Thereaction time is preferably from about 10 seconds to about 1 hour.

The α-olefin to ethylene molar ratio often bears importantly upon theproduction capacity of a reactor of any design—i.e., whether forsolution or gas phase production, etc.—for production of an ethylenebased copolymer (i.e.—a copolymer the molar ratio of which is 50% orgreater ethylene). The more ethylene input to a reactor in a given unitof time, the greater will be the amount of ethylene based copolymerproduct obtained in that same unit of time. Yet, polymers are designedfor a variety of end services and this design constraint dictates themolar percentage of incorporated α-olefin which must be obtained in thetargeted copolymer product. The “catalyst reactive ratio (r₁)” of acatalyst system defines the property of the system of assimilating anethylene monomer into a polymer molecule chain in preference to aparticular α-olefin comonomer. The larger the r₁ number, the greater thepreference of the catalyst system for incorporating an ethylene monomerrather than a α-olefin monomer. Thus, to achieve a targeted α-olefinmonomer incorporation (c_(α)) in the product polymer, the higher the r₁value of a catalyst system, the larger must be the C_(α)/C₂ molar ratioof monomers used in the reactor, and as the C_(α)/C₂ ratio increases thelower is the production capacity of the reactor.

To achieve a desired level of α-olefin monomer incorporation in acopolymer product, as can be seen, it is often desired to have acatalyst system which can achieve a low molar ratio of C_(α)/C₂, i.e., acatalyst system with a low r₁ is desired. For example, with reference to1-butene, the catalyst systems of this invention wherein the titaniummetal compound has a tetramethyl substitute cyclopentadienyl ligandgenerally exhibit an r₁ value of 6 or less, and typically of 5 or less.Thus, with catalyst systems of this invention an α-olefin incorporationof greater than 20 wt. % can be achieved at a C_(α)/C₂ ratio of 2.0 orless, and typically of about 1.6.

In addition to the benefits of increased reactor productivity which, fora copolymer of a targeted α-olefin incorporation level, which a catalystsystem of lower r₁ values allows, other significant additional benefitsensue from a low r₁ value. Recovery of unreacted monomer, particularlyα-olefin monomer for later reuse adds significantly to production cost.By use of the catalyst systems. identified by this invention, the costof unreacted α-olefin monomer recovery may be reduced significantlysince a smaller quantity of α-olefin monomer can be used to achieve thesame target level of α-olefin incorporation.

Further, since it is the ratio of C_(α)/C₂ in the medium whereinpolymerization occurs which is critical (i.e., liquid phase, gas phase,or super critical fluid phase, etc.) the low r₁ values for the catalystsystems of this invention permit the catalyst systems to be used in awider variety of polymerization procedures than was heretofore believedto be practically possible. Praticularily within this range ofpossibilities is that of the gas phase polymerization of an ethyleneα-olefin copolymer of a greater than heretofore believed possible levelof α-olefin incorporation.

Without limiting in any way the scope of the invention, one means forcarrying out the process of the present invention for production of acopolymer is as follows: in a stirred-tank reactor liquid α-olefinmonomer is introduced, such as 1-butene. The catalyst system isintroduced via nozzles in either the vapor or liquid phase. Feedethylene gas is introduced either into the vapor phase of the reactor,or sparged into the liquid phase as is well known in the art. Thereactor contains a liquid phase composed substantially of liquidα-olefin comonomer, together with dissolved ethylene gas, and a vaporphase containing vapors of all monomers. The reactor temperature andpressure may be controlled via reflux of vaporizing α-olefin monomer(autorefrigeration), as well as by cooling coils, jackets etc. Thepolymerization rate is controlled by the concentration of catalyst. Theethylene content of the polymer product is determined by the ratio ofethylene to α-olefin comonomer in the reactor, which is controlled bymanipulating the relative feed rates of these components to the reactor.

As before noted, a catalyst system wherein the Group IV B transitionmetal component is titanium has the ability to incorporate high contentsof α-olefin comonomers. Accordingly, the selection of the titanium metalcomponent to have the cyclopentadienyl group to be tetramethylsubstituted and to have an amido group bridged through its nitrogen atomto the cyclopentadienyl ring wherein the nitrogen of the amido group isbonded through a 10° or 2° carbon atom to an aliphatic or alicyclichydrocarbyl group, most preferably an alicyclic hydrocarbyl group isanother parameter which may be utilized as a control over the α-olefincontent of the ethylene-α-olefin copolymer within a reasonable ratio ofethylene to α-olefin comonomer. For reasons already explained, in theproduction of an ethylene-α-olefin copolymer a molar ratio of ethyleneto α-olefin of 2.0 or less is preferred, and a ratio of 1.6 or less ismore preferred.

EXAMPLES

In the examples which illustrate the practice of the invention theanalytical techniques described below were employed for the analysis ofthe resulting polyolefin products. Molecular weight determinations forpolyolefin products were made by Gel Permeation Chromatography (GPC)according to the following technique. Molecular weights and molecularweight distributions were measured using a Waters 150 gel permeationchromatograph equipped with a differential refractive index (DRI)detector and a Chromatix KMX-6 on-line light scattering photometer. Thesystem was used at 135° C. with 1,2,4-trichlorobenzene as the mobilephase. Shodex (Showa Denko America, Inc.) polystyrene gel columns 802,803, 804 and 805 were used. This technique is discussed in “LiquidChromatography of Polymers and Related Materials III”, J. Cazes editor,Marcel Dekker. 1981, p. 207, which is incorporated herein by reference.No corrections for column spreading were employed; however, data ongenerally accepted standards, e.g. National Bureau of StandardsPolyethylene 1484 and anionically produced hydrogenated polyisoprenes(an alternating ethylene-propylene copolymer) demonstrated that suchcorrections on Mw/Mn (=MWD) were less than 0.05 units. Mw/Mn wascalculated from elution times. The numerical analyses were performedusing the commercially available Beckman/CIS customized LALLS softwarein conjunction with the standard Gel Permeation package, run on a HP1000 computer.

The following examples are intended to illustrate specific embodimentsof the invention and are not intended to limit the scope of theinvention.

All procedures were performed under an inert atmosphere of helium ornitrogen. Solvent choices are often optional, for example, in most caseseither pentane or 30-60 petroleum ether can be interchanged. Thelithiated amides were prepared from the corresponding amines and eithern-BuLi or MeLi. Published methods for preparing LiHC₅Me₄ include C. M.Fendrick et al. Organometallics, 3, 819 (1984) and F. H. Köhler and K.H. Doll, Z. Naturforich, 376, 144 (1982). Other lithiated substitutedcyclopentadienyl compounds are typically prepared from the correspondingcyclopentadienyl ligand and n-BuLi or MeLi, or by reaction of MeLi withthe proper fulvene. TiCl₄, ZrCl₄ and HfCl₄ were purchased from eitherAldrich Chemical Company or Cerac. TiCl₄ was typically used in itsetherate form. The etherate, TiCl₄.2Et₂O, can be prepared by gingerlyadding TiCl₄ to diethylether. Amines, silanes, substituted andunsubstituted cyclopentadienyl compounds or precursors, and lithiumreagents were purchased from Aldrich Chemical Company or PetrarchSystems. Methylalumoxane was supplied by either Sherring or Ethyl Corp.

Further, since the full disclosure of U.S. application Ser. No.07/581,841 filed Sep. 13, 1990, now U.S. Pat. No. 5,096,867, has beenincorporated herein, the Examples hereof are identified by designationswhich are consistent with the Example designations of the incorporatedapplication. Examples of the incorporated application relating to the Zror Hf metal classes of a monocyclopentadienyl transition metal catalystsystem are not here repeated (which are Examples A to L) for sake ofbrevity. Accordingly, not verbatim repeated herein (but incorporated)are Examples A to L, and certain other double letter designated Examplesof the incorporated patent. Set forth verbatim herein as repeats ofExamples of the incorporated application are Examples AT, FT, IT, JT,40-47, 53-56, 58, 67 and 70.

Example AT

Compound AT:

Part 1. MePhSiCl₂ (14.9 g, 0.078 mol) was diluted with 250 ml of thf.Me₄HC₅Li (10.0 g, 0.078 mol) was slowly added as a solid. The reactionsolution was allowed to stir overnight. The solvent was removed via avacuum to a cold trap held at −196° C. Petroleum ether was added toprecipitate the LiCl. The mixture was filtered through Celite and thepentane was removed from the filtrate. MePhSi(Me₄C₅H)Cl (20.8 g, 0.075mol) was isolated as a yellow viscous liquid.

Part 2. LiHN-t-Bu (4.28 g, 0.054 mol) was dissolved in ˜100 ml of thf.MePhSi(C₅Me₄H)Cl (15.0 g, 0.054 mol) was added dropwise. The yellowsolution was allowed to stir overnight. The solvent was removed invacuo. Petroleum ether was added to precipitate the LiCl. The mixturewas filtered through Celite, and the filtrate was evaporated.MePhSi(C₅Me₄H)(NH-t-Bu) (16.6 g, 0.053 mol) was recovered as anextremely viscous liquid.

Part 3. MePhSi(C₅Me₄H)/(NH-t-Bu)(17.2 g, 0.055 mol) was diluted with ˜20ml of ether. n-BuLi (60 ml in hexane, 0.096 mol, 1.6 M) was slowly addedand the reaction mixture was allowed to stir for ˜3 hours. The solventwas removed in vacuo to yield 15.5 g (0.48 mol) of a pale tan solidformulated as Li₂[MePhSi(C₅Me₄)(N-t-Bu)].

Part 4. Li₂[MePhSi(C₅Me₄)(N-t-Bu) (8.75 g, 0.027 mol) was suspended in˜125 ml of cold ether (−30° C.). TiCl₄.2Et₂O(9.1 g, 0.027 mol) wasslowly added. The reaction was allowed to stir for several hours priorto removing the ether via vacuum. A mixture of toluene anddichloromethane was then added to solubilize the product. The mixturewas filtered through Celite to remove the LiCl. The solvent was largelyremoved via vacuum and petroleum ether was added. The mixture was cooledto maximize product precipitation. The crude product was filtered offand redissolved in toluene. The toluene insolubles were filtered off.The toluene was then reduced in volume and petroleum ether was added.The mixture was cooled to maximize precipitation prior to filtering off3.34 g (7.76 mmol) of the yellow solid MePhSi(C₅Me₄)/(N-t-Bu)TiCl₂.

Example FT

ComDound FT:

Part 1. (C₅Me₄H)SiMe₂Cl was prepared as described in Example BT for thepreparation of compound BT, Part 1.

Part 2. (C₅Me₄H)SiMe₂Cl (5.19 g, 0.024 mol) was slowly added to asolution of LiHNC₆H₁₁ (2.52 g, 0.024 mol) in ˜125 ml of thf. Thesolution was allowed to stir for several hours. The thf was removed viavacuum and petroleum ether was added to precipitate the LiCl which wasfiltered off. The solvent was removed from the filtrate via vacuumyielding 6.3 g (0.023 mol) of the yellow liquid, Me₂Si(C₅Me₄H)(HNC₆H₁₁).

Part 3. Me₂Si(C₅Me₄H)/(HNC₆H₁₁) (6.3 g, 0.023 mol) was diluted with ˜100ml of ether. MeLi (33 ml, 1.4 M in ether, 0.046 mol) was slowly addedand the mixture was allowed to stir for 0.5 hours prior to filtering offthe white solid. The solid was washed with ether and vacuum dried.Li₂[Me₂Si(C₅Me₄) (NC₆H₁₁)] was isolated in a 5.4 g (0.019 mol) yield.

Part 4. Li₂(Me₂Si(C₅Me₄)(NC₆H₁₁)] (2.57 g, 8.90 mmol) was suspended in˜50 ml of cold ether. TiCl₄.2Et₂O (3.0 g, 8.9 mmol) was slowly added andthe mixture was allowed to stir overnight. The solvent was removed viavacuum and a mixture of toluene and dichloromethane was added. Themixture was filtered through Celite to remove the LiCl byproduct. Thesolvent was removed from the filtrate and a small portion of toluene wasadded followed by petroleum ether. The mixture was chilled in order tomaximize precipitation. A brown solid was filtered off which wasinitially dissolved in hot toluene, filtered through Celite, and reducedin volume. Petroleum ether was then added. After refrigeration, an olivegreen solid was filtered off. This solid was recrystallized twice fromdichloromethane and petroleum ether to give a final yield of 0.94 g (2.4mmol) of the pale olive green solid, Me₂Si(C₅Me₄) (NC₆H₁₁)TiCl2.

Example IT

Compound IT:

Part 1. (C₅Me₄H)SiMe₂Cl was prepared as described in Example BT for thepreparation of Compound BT, part 1.

Part 2. (C₅Me₄H)SiMe₂Cl (10.0 g, 0.047 mol) was slowly added to asuspension of LiHN-t-Bu (3.68 g, 0.047 mol, ˜100 ml thf). The mixturewas stirred overnight. The thf was then removed via a vacuum to a coldtrap held at ˜196° C. Petroleum ether was added to precipitate out theLiCl. The mixture was filtered through Celite. The solvent was removedfrom the filtrate. Me₂Si(C₅Me₄H)/(NH-t-Bu) (11.14 g, 0.044 mol) wasisolated as a pale yellow liquid.

Part 3. Me₂Si(C₅Me₄H)(NH-t-Bu)(11.14 g, 0.044 mol) was diluted with ˜100ml of ether. MeLi (1.4 M, 64 ml, 0.090 mol) was slowly added. Themixture was allowed to stir for ½hour after the final addition of MeLi.The ether was reduced in volume prior to filtering off the product. Theproduct, [Me₂Si(C₅Me₄)(N-t-Bu)]Li₂, was washed with several smallportions of ether, then vacuum dried.

Part 4. (Me₂Si(C₅Me₄)-(N-t-Bu)Li₂ (6.6 g, 0.025 mol) was suspended incold ether. TiCl₄.2Et₂O (8.4 g, 0.025 mol) was slowly added and theresulting mixture was allowed to stir overnight. The ether was removedvia a vacuum to a cold trap held at −196° C. Methylene chloride wasadded to precipitate the LiCl. The mixture was filtered through Celite.The solvent was significantly reduced in volume and petroleum ether wasadded to precipitate the product. This mixture was refrigerated prior tofiltration in order to maximize precipitation.Me₂Si(C₅Me₄)-(N-t-Bu)-TiCl₂ was isolated (2.1 g, 5.7 mmol).

Example JT

Compound JT:

Part 1. (C₅Me₄H)SiMe₂Cl was prepared as described in Example BT for thepreparation of Compound BT, Part 1.

Part 2. (C₅Me₄H)SiMe₂Cl (8.0 g, 0.037 mol) was slowly added to asuspension of LiHNC₁₂H₂₃ (C₁₂H₂₃=cyclododecyl, 7.0 g, 0.037 mol, ˜80 mlthf). The mixture was stirred overnight. The thf was then removed via avacuum to a cold trap held at −196° C. Petroleum ether and toluene wasadded to precipitate the LiCl. The mixture was filtered through Celite.The solvent was removed from the filtrate. Me₂Si(C₅Me₄H)-(NHC₁₂H₂₃)(11.8 g, 0.033 mol) was isolated as a pale yellow liquid.

Part 3. Me₂Si(C₅Me₄H)-(NHC₁₂H₂₃) (11.9 g, 0.033 mol) was diluted with˜150 ml of ether. MeLi (1.4 M, 47 ml, 0.066 mol) was slowly added. Themixture was allowed to stir for 2 hours after the final addition ofMeLi. The ether was reduced in volume prior to filtering off theproduct. The product, [Me₂Si(C₅Me₄)(NC₁₂H₂₃)]Li₂, was washed withseveral small portions of ether, then vacuum dried to yield 11.1 g(0.030 mol) of product.

Part 4. [Me₂Si(C₅Me₄) (NC₁₂H₂₃)]Li₂ (3.0 g, 0.008 mol) was suspended incold ether. TiCl₄.2Et₂O (2.7 g, 0.008 mol) was slowly added and theresulting mixture was allowed to stir overnight. The ether was removedvia a vacuum to a cold trap held at −196° C. Methylene chloride wasadded to precipitate the LiCl. The mixture was filtered through Celite.The solvent was significantly reduced in volume and petroleum ether wasadded to precipitate the product. This mixture was refrigerated prior tofiltration in order to maximize precipitation. The solid collected wasrecrystallized from methylene chloride and Me₂Si(C₅Me₄) (Nc₁₂H₂₃)TiCl₂was isolated (1.0 g, 2.1 mmol).

Example KT

Compound KT:

Part 1. (C₅Me₄H) SiMe₂Cl was prepared as described in Example A for thepreparation of compound A, Part 1.

Part 2. (C₅Me₄H)SiMe₂Cl (6.0 g, 0.0279 mol) was diluted in 200 ml ofthf. LiHNC₁₂H₂₅ (C₁₂H₂₅=n-dodecyl, 5.33 g, 0.0279 ml) was slowly addedand the mixture was allowed to stir for 3 hours. The thf was removed invacuo and 200 ml ether was added.

To this solution, MeLi (1.4 M, 34 ml, 0.0476 mol) was slowly added. Uponcompletion of the reaction, a small amount of TiCl₄.2Et₂O was added toscavenge the excess MeLi. The solution was then cooled to −30° C. and anadditional 7.75 g (0.030 mol) of TiCl₄.2Et₂O was added. The mixture wasallowed to stir overnight. The solvent was removed and pentane wasadded. The resulting mixture was filtered through Celite to remove theLiCl. The filtrate was reduced in volume and chilled to inducecrystalization of the product. Filtration yielded 4.2 g (0.0087 mol)Me₂Si(C₅Me₄) (NC₁₂H₂₅)TiCl₂.

Example LT

Compound LT:

Part 1. (C₅Me₄H)SiMe₂Cl was prepared as described in Example A for thepreparation of compound A, Part 1.

Part 2. (C_(Me) ₄H)SiMe₂Cl (12.0 g, 0.056 mol) was diluted with 300 mlof thf. LiHNC₈H₁₅(C₈H₁₅=cyclooctyl, 7.42 g, (0.056 mol) was slowly addedand the mixture was allowed to stir overnight. The reaction product,Me₂Si(C₅Me₄H) (HNC₈H₁₅) was not isolated. The thf was removed and 300 mlof diethyl ether was added. MeLi (1.12M, 105 ml, 0.118 mol) was slowlyadded to form the dilithiated salt, Li₂[Me₂Si(C₅Me₄) (NC₈H₁₅)]. Thismixture was cooled to −30° C., and TiCl₄.2Et₂O (19.14 g, 0.057 mol) wasslowly added. The resulting mixture was allowed to stir overnight. Theether was removed in vacuo, and pentane was added to solubilize theproduct. The mixture was filtered through Celite to remove the LiCl. Thefiltrate was reduced in volume and chilled to −40° C. to inducecrystallization of the product. Filtration yielded 7.9 g (0.019 mol) ofMe₂Si(C₅Me₄) (NC₈H₁₅)TiCl₂.

Example MT

Compound MT:

Part 1. (C₅Me₄H)SiMe₂Cl was prepared as described in Example A for thepreparation of compound A, Part 1.

Part 2. (C₅Me₄H)SiMe₂Cl (6.0 g, 0.028 mol) was diluted with 150 ml ofthf. LiHNC₈H₁₇ (C₈H₁₇=n-octyl, 3.7 g, 0.030 mol) was slowly added. Themixture was allowed to stir overnight. The reaction product,Me₂Si(C₅Me₄H)(HNC₈H₁₇) was not isolated prior to adding MeLi (2.1 M, 35ml, 0.074 mol) to give Li₂[Me₂Si(C₅Me₄) (NC₈H₁₇)]. The solvent wasremoved via vacuum and replaced with diethyl ether, then cooled to −30°C. TiCl₄.2Et₂O (8.46 g, 0.025 mol) was slowly added and the mixture wasallowed to stir overnight. The solvent was removed in vacuo andmethylene chloride was used to solubilize the product. The solventmixure was filtered through Celite to remove the LiCl. The filtrate wasevaporated down to dryness and pentane was added. The pentane solublefraction was cooled to −40° C. to induce crystallization of the product.After filtration, Me₂Si(C₅Me₄)(NC₈H₁₇)TiCl₂ was isolated (1.8 g, 0.0042mol).

Example NT

Compound NT:

Part 1. (C₅Me₄H)SiMe₂Cl was prepared as described in Example A for thepreparation of compound A, Part 1.

Part 2. (C₅Me₄H)SiMe₂Cl (6.0 g, 0.028 mol) was diluted in 150 ml of thf.LiHNC₆H₁₃ (C₆H₁₃=n-hexyl, 2.99 g, 0.028 mol) was slowly added. Themixture was allowed to stir overnight. The thf was removed via vacuumand replaced with diethyl ether. The reaction product Me₂Si(C₅Me₄H)(HNC₆H₁₃) was not isolated prior to adding MeLi (1.4 M, 45 ml, 0.063mol) to give Li₂[Me₂Si(C₅Me₄) (NC₆H₁₃)]. The resulting mixture was thencooled to −30° C. TiCl₄.2Et₂ (8.6 g, 0.025 mol) was slowly added and themixture was allowed to stir overnight. The solvent was removed in vacuoand pentane was used to solubilize the product. The solvent mixture wasfiltered through Celite to remove the LiCl. The filtrate was reduced involume and cooled to −40° C. to induce crystallization of the product.While crystalline material appeared in the flask at −40° C., upon slightwarming, it dissolved back into solution and therefore could not beisolated by filtration. Me₂Si(C₅Me₄) (NC₆H₁₃)TiCl₂ was isolated in anoil form by removing the solvent from the above solution. (4.0 g, 0.010mol).

Example OT

Compound OT:

Part 1. MePhSi(C₅Me₄H)Cl was prepared as described in Example AT for thepreparation of compound AT, Part 1.

Part 2. MePhSi(C₅Me₄H)Cl (6.0 g. 0.022 mol) was diluted with ether.LiHN-s-Bu (1.7 g, 0.022 mol) was slowly added and the mixture wasallowed to stir overnight. The solvent was removed and a mixture oftoluene and petroleum ether was added. This mixture was filtered throughCelite to remove the LiCl. The solvent was removed via vacuum leavingbehind the viscous liquid, MePhSi(C₅Me₄H) (HN-s-Bu). To this liquidwhich was diluted with ether, 28 ml (0.039 mol 1.4 M in ether) MeLi wasslowly added. After stirring overnight, a small portion of TiCl₄.2Et₂O(total of 5.86 g, 0.017 mol) was slowly added and the mixture wasallowed to stir overnight. The solvent was removed via vacuum,dichloromethane was added and the mixture was filtered through Celite.The filtrate was evaporated down producing a brown solid. Petroleumether was added and the mixture was filtered. The brown solid remainingon the filter stick was discarded and the filtrate was reduced in volumeand refrigerated to maximize precipitation. After filtration and washingwith cold aliquots of petroleum ether, a dark mustard yellow solid wasisolated and identified as MePhSi(C₅Me₄) (N-s-Bu)TiCl₂ (2.1 g, 4.9mmol).

Example PT

Compound PT:

Part 1. MePhSi(C₅Me₄H)Cl was prepared as described in Example AT for thepreparation of compound AT, Part 1.

Part 2. MePhSi(C₅Me₄H)Cl (6.0 g, 0.022 mol) was diluted with either.LiHN-n-Bu (1.7 g, 0.022 mol) was slowly added and the mixture wasallowed to stir overnight. The solvent was removed via vacuum and amixture of toluene and petroleum ether was added. This was filteredthrough Celite to remove the LiCl. The solvent was removed from thefiltrate leaving behind a viscous yellow liquid which was diluted withether. To this, 28 ml of MeLi (1.4 M in ether, 0.038 mol) was added andthe mixture was allowed to stir overnight. A small portion ofTiCl₄.2Et₂O (total of 5.7 g, 0.017 mol) was slowly added. In spite ofthe slow addition, the highly exothermic reaction bumped, thus someproduct loss occurred at this point in the reaction. The remainingmixture was stirred overnight. The solvent was then removed via vacuum.Dichloromethane was added and the mixture was filtered through Celite toremove the LiCl. The solvent was removed and petroleum ether was added.The mixture was refrigerated to maximize precipitation. Filtrationproduced a yellow-brown solid which was recrystallized from petroleumether. The final filtration produced 2.0 g (4.6 mmol) of MePhSi(Me₄C₅)(N-n-Bu)TiCl₂.

Example QT

Compound QT:

Part 1. (C₅Me₄H)SiMe₂Cl was prepared as described in Example A for thepreparation of compound A, Part 1.

Part 2. (C₅Me₄H)SiMe₂Cl (9.0 g, 0.042 mol) was diluted in ether.LiHN-s-Bu (3.31 g, 0.042 mol) was slowly added and the mixture wasallowed to stir overnight. The solvent was removed via vacuum andpetroleum ether was added. This mixture was filtered through Celite toremove the LiCl. The solvent was removed from the filtrate leavingbehind the pale yellow liquid, Me₂Si(C₅Me₄H)(HN-s-Bu) (10.0 g, 0.040mol).

Part 3. Me₂Si(C₅Me₄H)(HN-s-Bu) (10.0 g, 0.040 mol) was diluted withether. MeLi (58 ml, 1.4 M in ether, 0.081 mol) was added and the mixturewas allowed to stir overnight. The solvent was reduced in volume and thewhite solid was filtered off and washed with small portions of ether.Li₂[Me₂Si(C₅Me₄) (N-s-Bu)] (10.1 g, 0.038 mol) was isolated after vacuumdrying.

Part 4. Li₂[Me₂Si(C₅Me₄)(N-s-Bu)] (7.0 g, 0.027 mol) was suspended incold ether. TiCl₄.2Et₂O (8.98 g, 0.027 mol) was slowly added and themixture was allowed to stir overnight. The solvent was removed viavacuum and dichloromethane was added. The mixture was filtered throughCelite to remove the LiCl. The filtrate was reduced in volume andpetroleum ether was added. This mixture was refrigerated to maximizeprecipitation prior to filtering off the olive green solid. The solidwas recrystallized from dichloromethane and petroleum ether yielding 2.4g (6.5 mmol) of the yellow solid, Me₂Si(C₅Me₄)(N-s-Bu)TiCl₂.

Example RT

Compound RT:

Part 1. (C₅Me₄H)SiMe₂Cl was prepared as described in Example A for thepreparation of compound A, Part 1.

Part 2. (C₅Me₄H)SiMe₂Cl (8.0 g, 0.037 mol) was diluted with ether.LiHN-n-Bu (2.95 g, 0.037 mol) was slowly added and the mixture wasallowed to stir overnight. The solvent was removed via vacuum andpetroleum ether was added. The mixture was filtered through Celite toremove the LiCl. The solvent was removed from the filtrate leavingbehind the yellow liquid, Me₂Si(C₅Me₄H)(HN-n-Bu) (8.6 g, 0.034 mol).

Part 3. Me₂Si(C₅Me₄H) (HN-n-Bu) (8.6 g, 0.034 mol) was diluted withether. MeLi (50 ml, 1.4 M in ether, 0.070 mol) was slowly added and themixture was allowed to stir for two hours. The solvent was removedleaving behind 10.2 g (0.035 mol) of the yellow solid,Li₂[Me₂Si(C₅Me₄)(N-n-Bu)].⅓Et₂O.

Part 4. Li₂[Me₂Si(C₅Me₄) (N-n-Bu)]. ⅓Et₂O (6.0 g, 0.021 mol) wassuspended in cold ether. TiCl₄.2Et₂O (7.04 g, 0.0212 mol) was slowlyadded and the mixture was allowed to stir overnight. The solvent wasremoved and dichloromethane was added. The mixture was filtered throughCelite to remove the Licl. The filtrate was reduced in volume andpetroleum ether was added. The mixture was refrigerated to maximizeprecipitation prior to filtering off a mixture of dark powder and yellowcrystals. The material was redissolved in a mixture of dichloromethaneand toluene. A small portion of petroleum ether was added and the brownprecipitate was filtered off and discarded. The filtrate was reduced involume, additional petroleum ether was added and the mixture was placedback in the refrigerator. Later, 3.65 g of the maize yellow solid,Me₂Si(C₅Me₄) (N-n-Bu)TiCl₂ was filtered off.

Example ST

Compound ST:

Part 1. Me₂SiCl₂ (210 ml, 1.25 mol) was diluted with a mixture of etherand thf. LiMeC₅H₄ (25 g, 0.29 mol) was slowly added, and the resultingmixture was allowed to stir for a few hours, after which time thesolvent was removed in vacuo. Pentane was added to precipitate the LiCl,and the mixture was filtered through Celite. The pentane was removedfrom the filtrate leaving behind a pale yellow liquid, Me₂Si(MeC₅H₄)Cl.

Part 2. Me₂Si(MeC₅H₄)Cl (10.0 g, 0.058 mol) was diluted with a mixtureof ether and thf. To this, LiHNC₁₂H₂₃ (11.0 g, 0.058 mol). was slowlyadded. The mixture was allowed to stir overnight. The solvent wasremoved via vacuum and toluene and pentane were added to precipitate theLiCl. The solvent was removed from the filtrate leaving behind a paleyellow liquid, Me₂Si-(MeC₅H₄) (HNC₁₂H₂₃) (18.4 g, 0.058 mol)

Part 3. Me₂Si(MeC₅H₄) (HNC₁₂H₂₃) (18.4 g, 0.058 mol) was diluted inether. MeLi (1.4 M in ether, 82 ml, 0.115 mol) was slowly added. thereaction was allowed to stir for several hours before reducing themixture in volume and then filtering off the white solid,Li₂[Me₂Si(MeC₅H₃) (NC₁₂H₂₃)] (14.3 g, 0.043 mol).

Part 4. Li₂[Me₂Si(MeC₅H₃)(NC₁₂H₂₃)] (7.7 g, 0.023 mol) was suspended incold ether. TiCl₄.2Et₂ (7.8 g, 0.023 mol) was slowly added and themixture was allowed to stir overnight. The solvent was removed viavacuum. Dichloromethane was added and the mixture was filtered throughCelite. The dichloromethane was reduced in volume and petroleum etherwas added to maximize precipitation. This mixture was then refrigeratedfor a short period of time prior to filtering off a yellow/green solididentified as Me₂Si(MeC₅H₃) (NC₁₂H₂₃)TiCl₂ (5.87 g, 0.013 mol).

Example TT

Compound TT:

Part 1. Me₂SiCl₂ (7.5 ml, 0.062 mol) was diluted with ˜30 ml of thf. At-BuH₄C₅Li solution (7.29 g, 0.057 mol, ˜100 ml of thf) was slowlyadded, and the resulting mixture was allowed to stir overnight. The thfwas removed in vacuo. Pentane was add to precipitate the LiCl, and themixture was filtered through Celite. The pentane was removed from thefiltrate leaving behind a pale yellow liquid, Me₂Si(t-BuC₅H₄)Cl (10.4 g,0.048 mol).

Part 2. Me₂Si(t-BuC₅H₄)Cl (8.0 g, 0.037 mol) was diluted with thf. Tothis, LiHNC₁₂H₂₃ (7.0 g, 0.037 mol) was slowly added. The mixture wasallowed to stir overnight. The solvent was removed via vacuum andtoluene was added to precipitate the LiCl. The toluene was removed fromthe filtrate leaving behind a pale yellow liquid, Me₂Si(t-BuC₅H₄)(HNC₁₂H₂₃) (12.7 g, 0.035 mol).

Part. 3 Me₂Si(t-BuC₅H₄) (HCN₁₂H₂₃) (12.7 g, 0.035 mol) was diluted withether. To this, MeLi (1.4 M in ether, 50 ml, 0.070 mol) was slowlyadded. This was allowed to stir for two hours prior to removing thesolvent via vacuum. The product, Li₂[Me₂Si(t-BuC₅H₃) (NC₁₂H₂₃)] (11.1 g,0.030 mol) was isolated.

Part 4. Li₂[Me₂si(t-BuC₅H₃)(NC₁₂H₂₃)] (10.9 g, 0.029 mol) was suspendedin cold ether. TiCl₄.2ET₂O (9.9 g, 0.029 mol) was slowly added and themixture was allowed to stir overnight. The solvent was removed viavacuum. Dichloromethane was added and the mixture was filtered throughCelite. The solvent was removed and pentane was added. The product iscompletely soluble in pentane. This solution was passed through a columncontaining a top layer of silica and a bottom layer of Celite. Thefiltrate was then evaporated down to an olive green colored solididentified as Me₂Si(t-BuC₅H₃) (NC₁₂H₂₃)TiCl₂ (5.27 g, 0.011 mol).

Example UT

Compound UT

Me₂Si(C₅Me₄) (NC₁₂H₂₃)TiMe₂ was prepared by adding a stoichiometricamount of MeLi (1.4 M in ether) to Me₂Si(C₅Me₄) (NC₁₂H₂₃) TiCl₂(Compound JT from Example JT) suspended in ether. The white solidrecrystallized from toluene and petroleum ether was isolated in a 57%yield.

Example 40

Polymerization—Compound AT

The polymerization run was performed in a 1 liter autoclave reactorequipped with a paddle stirrer, an external water jacket for temperaturecontrol, a regulated supply of dry nitrogen, ethylene, propylene,1-butene and hexane, and a septum inlet for introduction of othersolvents or comonomers, transition metal compound and alumoxanesolutions. The reactor was dried and degassed thoroughly prior to use. Atypical run consisted of injecting 400 ml of toluene, 5 ml of 1.0 M MAO,0.206 mg compound AT (0.2 ml of a 10.3 mg in 10 ml of toluene solution)into the reactor. The reactor was then heated to 80° C. and the ethylene(60 psi) was introduced into the system. The polymerization reaction waslimited to 30 minutes. The reaction was ceased by rapidly cooling andventing the system. The solvent was evaporated off of the polymer by astream of nitrogen. Polyethylene was recovered (11.8 g, MW=279,700,MWD=2.676).

Example 41

Polymerization—Compound AT

Using the same reactor design and general procedure as described inExample 40, 400 ml of toluene, 5.0 ml of 1.0 M MAO, and 0.2 ml of apreactivated compound AT solution (10.3 mg of compound AT dissolved in9.5 ml of toluene and 0.5 ml of 1.0 M MAO) were added to the reactor.The reactor was heated to 80° C., the ethylene was introduced (60 psi),and the reaction was allowed to run for 30 minutes, followed by rapidlycooling and venting the system. After evaporation of the solvent, 14.5 gof polyethylene was recovered (MW=406,100, MWD=2.486).

Example 42

Polymerization—Compound AT

Using the same reactor design and general procedure described in Example40, 300 ml of toluene, 100 ml of 1-hexene, 7.0 ml of 1.0 M MAO, and 1.03mg of compound AT (1.0 ml of 10.3 mg in 10 ml of toluene solution) wereadded to the reactor. The reactor was heated at 80° C., the ethylene wasintroduced (65 psi), and the reaction was allowed to run for 10 minutes,followed by rapidly cooling and venting the system. After evaporation ofthe toluene, 48.6 g of an ethylene-1-hexene copolymer was recovered(MW=98,500, MWD=1.745, 117 SCB/1000C by ¹³C NMR).

Example 43

Polymerization—Compound AT

Using the same reactor design and general procedure described in Example40, 375 ml of toluene, 25 ml of 1-hexene, 7.0 ml of 1.0 M MAO, and 1.03mg of compound AT (1.0 ml of a 10.3 mg in 10 ml of toluene solution)were added to the reactor. The reactor was heated at 80° C., theethylene was introduced (65 psi), and the reaction was allowed to runfor 10 minutes, followed by rapidly cooling and venting the system.After evaporation of the toluene, 29.2 g of an ethylene-1-hexenecopolymer was recovered (MW=129,800, MWD=2.557, 53.0 SCB/1000C by ¹³CNMR).

Example 44

Polymerization—Compound AT

Using the same reactor design and general procedure described in Example40, 375 ml of toluene, 25 ml of 1-hexene, 7.0 ml of 1.0 M MAO, and 1.03mg of compound AT (1.0 ml of 10.3 mg in 10 ml of toluene solution) wereadded to the reactor. The reactor was heated at 50° C., the ethylene wasintroduced (65 psi), and the reaction was allowed to run for 10 minutes,followed by rapidly cooling and venting the system. After evaporation ofthe toluene, 15.0 g of an ethylene-1-hexene copolymer was recovered(MW=310,000, MWD=2.579, 47.2 SCB/1000C by ¹³C NMR).

Example 45

Polymerization—Compound AT

Using the same reactor design and general procedure described in Example40, 300 ml of toluene, 100 ml of propylene, 7.0 ml of 1.0 M MAO, and2.06 mg of compound AT (2.0 ml of a 10.3 mg in 10 ml of toluenesolution) were added to the reactor. The reactor was heated at 80° C.,the ethylene was introduced (65 psi), and the reaction was allowed torun for 10 minutes, followed by rapidly cooling and venting the system.After evaporation of the toluene, 46.0 g of an ethylene-propylenecopolymer was recovered (MW=110,200, MWD=5.489, 20 wt % ethylene by IR).

Example 46

Polymerization—Compound AT

Using the same reactor design and general procedure described in Example40, 300 ml of toluene, 100 ml of 1-butene, 7.0 ml of 1.0 M MAO, and 1.03mg of compound AT (1.0 ml of a 10.3 mg in 10 ml of toluene solution)were added to the reactor. The reactor was heated at 80° C., theethylene was introduced (65 psi), and the reaction was allowed to runfor 10 minutes, followed by rapidly cooling and venting the system.After evaporation of the toluene, 35.1 g of an ethylene-1-butenecopolymer was recovered (MW=94,400, MWD=2.405, 165 SCB/1000C by ¹³CNMR).

Example 47

Polymerization—Compound AT

Using the same reactor design and general procedure described in Example40, 300 ml of toluene, 100 ml of 1-octene, 7.0 ml of 1.0 M MAO, and 1.04mg of compound AT (1.0 ml of a 10.4 mg in 10 ml of toluene solution)were added to the reactor. The reactor was heated at 80° C., theethylene was introduced (65 psi), and the reaction was allowed to runfor 10 minutes, followed by rapidly cooling and venting the system.After evaporation of the toluene, 30.6 g of an ethylene-1-octenecopolymer was recovered (MW=73,100, MWD=2.552, 77.7 SCB/1000C by ¹³CNMR).

Example 53

Polymerization—Compound AT

The polymerization was performed in a stirred 100 ml stainless steelautoclave which was equipped to perform polymerizations at temperaturesup to 300° C. and pressures up to 2500 bar. The reactor was evacuated,purged with nitrogen, purged with ethylene and heated to 200° C.1-hexene (75 ml) was added to the reactor under ethylene pressure. Astock solution of compound AT was prepared by dissolving 6.5 mg ofcompound AT in 12.5 ml of toluene. The test solution was prepared byadding 1.0 ml of the compound AT stock solution to 1.9 ml of 1.0 M MAOsolution, followed by 7.1 ml of toluene. The test solution (0.43 ml) wastransferred by nitrogen pressure into a constant-volume injection tube.The autoclave was pressurized with ethylene to 1748 bar and was stirredat 1800 rpm. The test solution was injected into the autoclave withexcess pressure, at which time a temperature rise of 16° C. wasobserved. The temperature and pressure were recorded continuously for120 seconds, at which time the contents of the autoclave were rapidlyvented into a receiving vessel. The reactor was washed with xylene torecover any polymer remaining within. These washings were combined withthe polymer released when the reactor was vented. Precipitation of thepolymer from the mixture by addition of acetone yielded 2.7 g of polymer(MW=64,000, MWD=3.16, 14.7 SCB/1000C by IR).

Example 54

Polymerization—Compound AT

For this Example a stirred 1 L steel autoclave reaction vessel which wasequipped to perform continuous Ziegler polymerization reactions atpressures to 2500 bar and temperatures up to 300° C. was used. Thereaction system was supplied with a thermocouple and pressure transducerto measure temperature and pressure continuously, and with means tosupply continuously purified compressed ethylene and 1-butene (orpropylene). Equipment for continuously introducing a measured flow ofcatalysts solution, and equipment for rapidly venting and quenching thereaction, and of collecting the polymer product were also a part of thereaction system. The polymeriz ation was performed with a molar ratio ofbutene-1 ethylene to of 1.6 without the addition of a solvent. Thetemperature of the cleaned reactor containing ethylene and 1-butene wasequilibrated at the desired reaction temperature of 180° C. The catalystsolution was prepared by mixing 0.888 g of solid compound AT with 0.67 Lof a 30 wt % methylalumoxane solution in 4.3 L of toluene in an inertatmosphere. This catalyst solution was continuously fed by a highpressure pump into the reactor at a rate of 0.56 L/hr which resulted ina temperature of 180° C. in the reactor. During this run, ethylene and1-butene were pressured into the autoclave at a total pressure of 1300bar. The reactor contents were stirred at 1000 rpm. The yield of polymerproducts was 3.9 kg/hr of an ethylene-1-butane copolymer which had aweight average molecular weight of 50,200, a molecular weightdistribution of 2.36 and 60.1 SCB/1000C as measured by ¹³C NMR.

Example 55

Polymerization—Compound AT

Using the same reactor design as described in Example 54, and using amolar ratio of ethylene to propylene of 2.6 without the addition of asolvent. The temperature of a cleaned reactor containing ethylene andpropylene was equilibrated at the desired reaction temperature of 140°C. The catalyst solution was prepared by mixing 0.779 g of solidcompound AT with 0.5 L of a 30 wt % methylalumoxane solution in 24.5 Lof toluene in an inert atmosphere. This catalyst solution wascontinuously fed by a high pressure pump into the reactor at a rate of0.9 L/hr which resulted in a temperature of 140° C. in the reactor.During this run, ethylene and propylene were pressured into theautoclave at a total pressure of 2200 bar. The reactor contents werestirred at 1000 rpm. The yield of polymer product was 2.3 kg/hr of anethylene-propylene copolymer which had a weight average molecular weightof 102,700, a molecular weight distribution of 2.208 and a density of0.863 g/cc.

Example 56

Polymerization—Compound FT

Using the same reactor design as described in Example 54, and using amolar ratio of ethylene to 1-butane of 1.6 without the addition of asolvent. The temperature of the cleaned reactor containin butane-1 andethylene was equilibrated at the desired reaction temperature of 180° C.The catalyst solution was prepared by mixing 0.859 g of solid FT with 30wt % methylalumoxane solution and toluene such that the catalystconcentration was 0.162 g/L with an Al/M molar ratio of 1200. Thepreparation was done under an inert atmosphere. This catalyst solutionwas continuously fed by a high pressure pump into the reactor at a rateof 1.15 L/hr which resulted in a temperature of 180° C. in the reactor.During this run, ethylene and 1-butene were pressured into the autoclaveat a total pressure of 1300. The reactor contents were stirred at 1000rpm. The yield of polymer product was 3.9 kg/hr of an ethylene-1-butenecopolymer which had a weight average molecular weight of 61,400, amolecular weight distribution of 2.607 and 104.8 SCB/1000C by ¹³C NMR.

Example 58

Polymerization—Compound AT

Using the same reactor design as described in Example 54, and using amolar ratio of butene-1 to ethylene of 1.6 without the addition of asolvent, the temperature of the cleaned reactor containing ethylene and1-butene was equilibrated at the desired reaction temperature of 170° C.The catalyst solution was prepared by mixing 0.925 g of solid compoundAT with 2 L of a 10 wt % methylalumoxane solution in 8 L of toluene inan inert atmosphere. This catalyst solution was continuously fed by ahigh pressure pump into the reactor at a rate of 0.28 L/hr whichresulted in a temperature of 170° C. in the reactor. During this run,ethylene and 1-butene were pressured into the autoclave at a totalpressure of 1300 bar. The reactor contents were stirred at 1000 rpm. Theyield of polymer product was 3.7 kg/hr of an ethylene-1-butane copolymerwhich had a weight average molecular weight of 69,500, a molecularweight distribution of 2.049 and 35.7 SCB/1000C by ¹³C NMR.

Example 67

Polymerization—Compound IT

Using the same reactor design as described in Example 54, and using amolar ratio of ethylene to 1-butene of 1.6 without the addition of asolvent, the temperature of the cleaned reactor containing ethylene and1-butene was equilibrated at the desired reaction temperature of 180° C.The catalyst solution was prepared by mixing 1.94 g of solid compound ITwith 30 wt % methylalumoxane solution and toluene such that the catalystconcentration was 0.388 g/L and the Al/M molar ratio was 600. Thepreparation was done under an inert atmosphere. This catalyst solutionwas continuously fed by a high pressure pump into the reactor at a rateof 0.42 L/hr which resulted in a temperature of 180° C. in the reactor.During this run, ethylene and 1-butene were pressured into the autoclaveat a total pressure of 1300 bar. The reactor contents were stirred at1000 rpm. The yield of polymer product was 3.9 kg/hr of anethylene-1-butene copolymer which had a weight average molecular weightof 50,800, a molecular weight distribution of 2.467 and 69 SCB/1000C asmeasured by ¹H NMR.

Example 70

Polymerization—Compound JT

Using the same reactor design as described in Example 54, and using amolar ratio of butane-1 ethylene of 1.6 without the addition of asolvent, the temperature of the cleaned reactor containing ethylene and1-butene was equilibrated at the desired reaction temperature of 180° C.The catalyst solution was prepared by mixing 1.78 g of solid compound JTwith 30 wt % methylalumoxane solution and toluene such that the catalystconcentration was 0.318 g/L and the Al/M molar ratio was 1400. Thepreparation was done under an inert atmosphere. This catalyst solutionwas continuously fed by a high pressure pump into the reactor at a rateof 0.55 L/hr which resulted in a temperature of 180° C. in the reactor.During thus run, ethylene and 1-butene were pressured into the autoclaveat a total pressure of 1300 bar. The reactor contents were stirred at1000 rpm. The yield of polymer product was 3.9 kg/hr of anethylene-1-butene copolymer which had a weight average molecular weightof 72,600, a molecular weight distribution of 2.385 and 110 SCB/1000C asmeasured by ¹H NMR.

Examples 71-86

Each of the compounds of Examples KT through TT were used to prepare anethylene-1-butene copolymer. The polymerization reactions were carriedout in the same reactor design as described in Example 54. With the soleexception of Example 83, all polymerizations were carried out using amolar ratio of 1-butene to ethylene of 1.6 without the addition of asolvent. In Example 83 a 1-butene to ethylene ratio of 2.0 was used. Thetemperature of the cleaned reactor containing ethylene and 1-butene wasequilibrated at the desired reaction temperature of 180° C.

The catalyst solution was prepared by mixing a specified amount of solidtransition metal component with a 30 weight percent methylalumoxanesolution and this catalyst solution was then further diluted in tolueneunder an inert atmosphere. This catalyst solution was continuously fedby a high pressure pump into the reactor at a rate which resulted in thedesired reactor temperature of 180° C., which was the polymerizationtemperature for all examples. The reactor contents were stirred at 1000rpm and a reactor mass flow rate of 40 kg/g was used for all examples.The reactor pressure was maintained at 1300 bar and no hydrogen wassupplied to the reactor. Exact run conditions including catalystpreparation [transition metal component (TMC) and amount (g), 30 weightpercent methylalumoxane (MAO) volume used (L), total volume of catalystsolution (L) and concentration (g TMC/L) and (g MAO/L)], catalyst feedrate (L/hr), polymer production rate (kg polymer/hr), molar Al/M ratio,productivity (kg polymer/g catalyst) and polymer characteristicsincluding weight average MW (Daltons), molecular weight distribution(MW/MN), melt index (10 g/10 min. at 190° C.), weight percent comonomer(determined by ¹H NMR or ¹³C NMR), and catalyst reactivity ratios (r₁)are collected in Table 1.

TABLE 1 Total Feed Production Ex. TMC MAO Vol TMC MAO Rate Rate # (g)(L) (L) (g/L) (g/L) (L/hr) (kg/hr) Al/M JT 71 0.540 0.4 10 0.0540 10.41.75 5.1 1595 KT 72 2.259 1.8  6 0.3765 78.3 0.51 3.9 1723 LT 73 1.4801.2  8 0.1850 39.2 0.46 4.0 1541 MT 74 1.366 1.0  6 0.2277 43.5 0.58 4.01398 FT 75 0.859 0.6   5.3 0.1620 29.5 1.14 4.2 1239 NT 76 1.441 1.2  80.1801 39.2 1.51 4.4 1485 AT 77 0.888 0.7  5 0.1776 35.0 0.56  4.35 1461OT 78 1.934 1.3  6 0.3223 54.4 0.62 4.3 1252 PT 79 1.900 1.3  6 0.316754.4 0.96  3.75 1274 IT 80 0.878 0.8 10 0.0878 19.6 0.84 4.3 1416 QT 810.953 0.9 10 0.0953 23.5 1.32 4.9 1565 RT 82 0.885 0.9 10 0.0885 23.51.68  4.65 1685 JT 83 1.494 0.5 10 0.1494 13.1 1.02 3.9  721 ST 84 3.0531.0 12 0.2540 21.8 0.51 2.9  643 TT 85 3.043 1.0 18 0.1690 14.5 1.11 2.6 701 UT 86 1.566 1.0  5 0.3132 52.2 0.35 5.0 1258 TMC Catalyst Ex.Productivity Productivity Wt % # (kg/g) (kg/g) MW MWD MI C4 Method τ1 JT71 54 0.28 63,600 2.363 11.3  42.0  1HNMR 4.4 KT 72 20 0.10 84,100 4.7753.3 40.8  1HNMR 4.7 LT 73 48 0.22 72,700 3.610 7.9 42.0  1HNMR 4.4 MT 7431 0.16 78,300 4.601 5.0 40.8  1HNMR 4.7 FT 75 23 0.12 61,400 2.60713.2  41.9  13CNMR 4.4 NT 76 16 0.07 85,400 3.971 3.6 44.0  1HNMR 4.1 AT77 44 0.22 50,200 2.360 19   24.0  13CNMR 10   OT 78 22 0.13 64,6002.494 8.1 43.6  13CNMR 4.1 PT 79 12 0.07 71,200 2.259 3.8 41.1  13CNMR4.6 IT 80 59 0.26 63,600 2.751 6.6 32.4  1HNMR 6.7 QT 81 39 0.16 64,5002.342 10   42.8  1HNMR 4.3 RT 82 31 0.12 71,100 2.262 8.8 40.0  1HNMR4.8 JT 83 26 0.29 78,200 2.617 5.2 40.8  1HNMR 4.6 ST 84 22 0.26 60,5002.183 8.5 17.62 13CNMR 15.0  TT 85 14 0.16 53,900 2.308 13.8  17.3813CNMR 15.2  UT 86 46 0.27 70,200 2.441 4.6 46.4  13CNMR 3.7

By appropriate selection of (1) Group IV B transition metal componentfor use in the catalyst system; (2) the type and amount of alumoxaneused; (3) the polymerization diluent type and volume; (4) reactiontemperature; and (5) reaction pressure, one may tailor the productpolymer to the weight average molecular weight value desired while stillmaintaining the molecular weight distribution to a value below about4.0.

The preferred polymerization diluents for practice of the process of theinvention are aromatic diluents, such as toluene, or alkanes, such ashexane.

From the above examples, particularly as collected in Table 1, itappears that for a catalyst system wherein the group IV B transitionmetal component is a titanium species of the following structure:

the nature of the R′ group dramatically influence the catalyticproperties of the system. For production of ethylene-α-olein copolymersof greatest comonomer content, at a selected ethylene to α-olefinmonomer ratio, R′ is preferably a non-aromatic substituent, such as analkyl or cycloalkyl substituent preferably bearing a primary orsecondary carbon atom attached to the nitrogen atom.

Further, from the above data, the nature of the Cp ligand structure of aTi metal component may be seen to influence the properties of thecatalyst system. Those Cp ligands which are not too sterically hinderedand which contain good electron donor groups, for example the Me₄C₅ligand, are preferred.

From the standpoint of having a catalyst system of high productivitywhich is capable of producing an ethylene-α-olefin copolymer of highmolecular weight and high comonomer incorporation, the most preferredtransition metal compound for the catalyst system is of the followingstructure:

wherein R¹ and R² are alkyl radicals having 1 to 6 carbon atoms, each Qis chlorine or methyl, and R′ is an aliphatic or alicyclic hydrocarbylhaving from 1 to 20 carbon atoms, preferably 3 to 20 carbon atoms.

The resins that are prepared in accordance with this invention can beused to make a variety of products including films and fibers.

The invention has been described with reference to its preferredembodiments. Those of ordinary skill in the art may, upon reading thisdisclosure, appreciate changes or modifications which do not depart fromthe scope and spirit of the invention as described above or claimedhereafter.

What is claimed is:
 1. A method for producing an ethylene-α-olefincopolymer of greater than 20 wt. % α-olefin content, comprising thesteps of: supplying ethylene and a α-olefin to a reaction zone at amolar ratio of α-olefin to ethylene of less than 2:1 in an amountsufficient to maintain a pressure within the reaction zone of from about0.019 to about 50,000 psia; introducing into contact with the ethyleneand α-olefin in the reaction zone a catalyst system comprising: (A) atransition metal component of the formula:

wherein R¹ and R² are each independently a hydrocarbyl radical, each Qand Q′ is independently a halide or alkyl radical, R′ is an aliphatic oralicyclic hydrocarbyl radical having from 3 to 20 carbon atoms and R′ iscovalently bonded to the nitrogen atom through a 1° or 2° carbon atom, Lis a neutral Lewis base where “w” denotes a number from 0 to 3; and (B)an alumoxane, said catalyst system being introduced in an amountsufficient to maintain a temperature within the reaction zone of fromabout −100 to about 300° C.
 2. The method of claim 1, wherein anethylene-α-olefin copolymer of greater than 30 wt. % 1-butene content isproduced, wherein the molar ratio of 1-butene to ethylene supplied tothe reaction zone is equal to or less than 1.6:1.